As a casing in which a substrate is received, for example, there has been known a casing according to a reference example illustrated in FIG. 7. The casing according to the reference example has, in a front surface thereof, a total of four slots for allowing insertion of substrates. Specifically, two slots are arrayed in each of an up-and-down direction and a right-and-left direction. Further, as illustrated in FIG. 8, in order to guide the substrates to be inserted, the casing according to the reference example includes three substrate guide members arrayed in the right-and-left direction.
Those substrate guide members are required to guide the substrate so that a terminal provided on a rear side in the casing and a terminal provided to the substrate are reliably connected to each other. Therefore, the substrate guide members are often designed so as to prevent formation of a sink mark in order to manufacture the substrate guide members with high accuracy by resin molding.
For example, in Patent Document 1, there is disclosed that a portion having a larger thickness than other portions, that is, a portion which is formed so as to have a large thickness is delayed in cooling time as compared to a portion which is not formed so as to have a large thickness, with the result that a sink mark may be formed in a surface.
Each of the substrate guide members according to the reference example is also designed without a large-thickness portion so as to prevent formation of the sink mark. In particular, the substrate guide member provided at the center has guide portions for guiding the substrate on both right and left sides. Therefore, the substrate guide member provided at the center often includes a large-thickness portion. Thus, as illustrated in FIG. 8, the substrate guide member provided at the center according to the reference example is sometimes manufactured by forming right and left divided pieces by resin molding and combining the divided pieces after the molding. In this manner, the formation of the sink mark caused by the large thickness of the substrate guide member provided at the center can be suppressed.